Improvement in test-valves



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Test-Valves.

Y Patented'Sept.22,1874.

llllllll v IIIIHII UNITED STATES PATENT OEEIOE.

EDWIN A. WOOD, OF UTICA, NEW YORK.

IMPROVEMENT IN TEST-VALVES.

Specification forming part of Letters Patent No. 155,355, datedSeptember 22, 1874; application filed April 20, 1874.

To all whom t may concern:

Be it known that I, EDWIN A. WOOD, of Utica, Oneida county and State ofNew York, have invented a new Test-Valve for Testing the Accuracy ofSteam and Pressure Gages, of which the following is a specification:

My invention is an improvement in gages for testing hydraulic pressure;and consists in a valve lworking vertically on a guide-pin, and having acavity in its upper side or surface to receive the point Or beak of ayoke by which the testing-weight is suspended, as hereinafter described.

Figure 1 is a perspective view of the testvalve iu its case. Fig. 2 is aside view of the test-valve, a part of the case being broken away. Fig.3 is a perspective view Of the base, showing the valve-opening. Fig. 4is a perspective view of the valve.

A is an outer oase. 1n Fig. 2 a part is broken away, as at al, to showthe parts within. Through the base of the case passes the pipe a2 forconnecting the valvechamber with the pump. B is the valve seat Or base.It

may be in the form of a ring, but I prefer that the upper part should beof a square form, B1, B2, B3, and B4, as seen in Fig. 2, for conveniencein calculating its area, which should be One inch square. lts upperedges are knife-edged. It should be made oi' steel, and well hardened,so that the valve may at al1 times t it closely. In the center of thevalve opening Or chamber is a steady or guide pin, B5, which extendshigher than the valveseat, for the purpose Of holding the valvecentrally over the Opening, as seen in Fig. 2. C is the valve, which maybe a iiat disk having a hole in its center on the under side O', so thatit may be slipped on the steady-pin B5. If the area of the valve-openingis just one inch square, a slit Or groove, B6, should be made, so thatthe force Of the water-pressure may be applied to the whole area ofthevalve,

which is inclosed by the seat. D is a yoke, whose curved beak or upperend rests in a central cavity Or depression in the upper surface ofvalve O, as seen in Fig. 1. The yoke is also curved at its lower end toadapt it to suspend a weight, E, and thus a vertical pressure will beexerted on the valve at a point directly over the guide or steady pin B.It hence results that, when the valve G rises, it is in a trueperpendicular line or direction, (the yoke and weight being raised withit,) and not in a curve, which would be the case if the pressure due tothe weight were exerted through the medium of a horizontal pivotedlever. Thus friction is reduced to a positive minimum, and acorresponding delicacy of test Of hydraulic pressure is secured.

The Operation is as follows: The pipe a? is connected with theforce-pump, and the steam or pressure gage to be tested is also attachedto the same pump. The yoke D has its upper point placed in the center ofthe upper surface of the valve, as seen in Fig. l, and a weight, which,with the valve O and yoke D, shall equal the pressure at which the gageis tO be tested, is suspended by its lower end, and, when the force Ofthe pump exceeds in the slightest degree the said weight, the valve Owill rise, and the index on the gage will at the same instant showwhether the gage is correct or not, and so by varying the weight thegage may be tested for any required pressure.

I claim as my invention- The combination, with the valve C, resting on aseat, B, working vertically on a central guide-pin, B5, and having acentral cavity in its upper side, of the weight-suspending yoke D, withcurved ends, all as shown and described, to operate as specified.

E. A. WOOD.

Witnesses:

FRANCIS G. WOOD, MORRIS H. AYLswORTH.

